It is presently understood that fish typically have a type of inner ear which can hear or sense sound transmitted through the water. It is further understood that fish have lateral line sensing organs which also sense sound. Such lateral line perception is apparently effective for lower frequencies, somewhere between about 4 hertz and 200 hertz. Inner ear sound sensing by fish is believed to be effective for frequencies in the range of between about 2 hertz to about 1000 hertz.
Lateral line sensing is apparently relied upon by fish to establish the relative origin of the sound by direction and depth and possibly even range. Specific sounds may be representative of a minnow and/or other aquatic creature which could be viewed by the fish as food. The In-Fisherman, Book #85, April '89, page 42-53. Fish are also believed to be responsive to magnetic and various other EMF fields.
A wide variety of fishing lures include mechanical or electronic means for attracting fish. For example, U.S. Pat. No. 4,223,467 (Hodges, Jr. et al.) discloses a fishing lure which intermittently buzzes and vibrates upon a change in attitude. U.S. Pat. No. 4,380,132 (Atkinson) discloses a plug with a water tight cavity within which a transducer transmits sound energy into the water. U.S. Pat. No. 2,757,475 (Pankove) discloses an early example of an electrically powered oscillator contained within a fishing lure, the power being generated by the action of water on dissimilar metal electrodes. U.S. Pat. No. 3,310,902 (Godby) discloses a fishing lure containing electrical components which generate a buzzing sound. U.S. Pat. No. 4,805,339 (Fuentes et al.) is directed to an electronically powered transducer fluid coupled to the water to transmit acoustic signals into the water in selected patterns. U.S. Pat. No. 4,583,313 (Dugan, Jr.) also shows a fishing lure housing circuitry to generate signals in a predetermined frequency band. U.S. Pat. Nos. 4,960,437 (Watson, et al) and 5,237,771 (Watson, et al) disclose signal generators of various types which may be associated in various ways with fishing lures. For example, they may be incorporated in a lure or they may be embodied as modules comprising a part of a plug, jig, bait rigging, or other lure.
Electronic lures are generally battery powered. They must thus be constructed either in disposable form, or to accommodate a replaceable battery. They must also accommodate associated electronic circuitry and switch mechanisms. Extending battery life has represented a technical challenge, as has the provision of reliable switching and miniaturization generally. It has only recently been practical to provide the advantages of electronic lures in miniature lure devices or in certain popular rigging arrangements, notably a Carolina rig.
Small operational signal-generating devices which can be associated with a lure, bait, spinner or jig structure to impart vibrational, acoustic or EMF energy to the water have been proposed. Such devices may be constructed to be readily added or subtracted to an overall fishing arrangement. It may also be configured to be either stationary or moveable, at the option of the fisherman. Such a device may transmit signals characteristic of currently preferred electronic lures; i.e., preselected in a pattern suggestive of food to fish as well as to provide signals for lateral line sensing by the fish. Ideally, the power supply, sound-generating and switching components of the device may be sufficiently compact and functional to improve the versatility of the practical applications of fish-attracting and/or fish-repelling electronic technology.